Flatten an array of arbitrarily nested arrays of objects into a flat array of objects

Program.cs

using System;
using System.Collections.Generic;

namespace FlatNestedArray
{
    class Program
    {
        static void Main(string[] args)
        {
            //[ [1, 2 , [3] ] ,4 ] -> [1,2,3,4]
            var nestedArrays = new object[] { new object[] { 1, 2, new object[] { 3 } }, 4 };
            List<object> flattenedList = new List<object>();

            FlattenArray(nestedArrays, ref flattenedList);

            flattenedList.ForEach(Console.WriteLine);
            Console.ReadLine();
        }

      
        /// <summary>
        /// Recursive function to flatten nested object arrays
        /// </summary>
        /// <param name="nestedArray">Nested array to flatten</param>
        /// <param name="flattenedList">Flattened result list</param>
        private static void FlattenArray(object [] nestedArray, ref List<object> flattenedList)
        {
            for (int i = 0; i < nestedArray.Length; i++)
            {
                var item = nestedArray[i];
                if (item is object[] array)
                {
                    FlattenArray(array, ref flattenedList);
                }
                else
                {
                    flattenedList.Add(item);
                }
            }
        }

    }
}